Hot top maintaining system for an ingot mold

ABSTRACT

The improved hot top maintaining system permits disposable hot top sideboards to extend above the ingot mold. A chill wedge is used in combination with a wedge plate positioned within converging grooves of adjacent sideboards. The chill wedge, after insertion, is flush against the wedge plate and the adjacent sideboards and provides a chill zone at the sideboard juncture so as to immediately solidify the metal and retain it within the hop top system.

United States Patent Rocher [451 May 7,1974

[ HOT TOP MAINTAINING SYSTEM FOR AN INGOT MOLD [75] Inventor: GeorgeRocher, Pittsburgh, Pa.

[73] Assignee: Metallurgical Exoproducts Corporation, McKees Rocks, Pa.

[22] Filed: Sept. 25, 1972 [21] Appl. No.: 291,655

[52] U.S. Cl. 249/106, 249/197 [51] Int. Cl B22d 7/10 [58] Field ofSearch 249/106, 197-202;

[56] References Cited UNITED STATES PATENTS 3,178,783 4/1965 Ednell etal 249/106 3,421,731 1/1969 Koch et al. 249/197 Primary Examiner-RobertD. Baldwin Attorney, Agent, or Firm-Webb, Burden, Robinson & Webb 7 57ABSTRACT The improved hot top maintaining system permits disposable hottop sideboards to extend above the ingot mold. A chill wedge is used incombination with a wedge plate positioned within converging grooves ofadjacent Sideboards. The chill wedge, after insertion, is flush againstthe wedge plate and the adjacent sideboards and provides a chill zone atthe sideboard juncture so as to immediately solidify the metal andretain it within the hop top system.

4 Claims, 7 Drawing Figures HOT TOP MAINTAINING SYSTEM FOR AN INGOT MOLDFIELD OF THE INVENTION My invention relates to hot top systems and, moreDESCRIPTION OF THE PRIOR ART Hot top systems employed in the teeming ofkilled steel ingots and the like are normally of the disposable typewhich comprises sideboards held in place within the ingot mold interiorby various clips, wedges, rods or the securing means or are of thepermanent type in which a refractory lined metal casing is positionedatop of the ingot mold. The permanent hot top system normally includesrefractory brick, but various forms of replaceable refractory liningshave been suggested.

In order for any hot top system to be effective, it must besubstantially filled with molten metal to provide an adequate reservoirof molten metal. Generally, the hot top volume varies from to percent ofthe total volume depending on the particular system. Therefore, for agiven mold size, a known and reoccurring ingot weight is obtained.However, it is often advantageous to alter the ingot weight for a givenmold size to provide particular slab cuts or bloom cuts necessary tomake an ordered weight. Without flexibility for a given mold size, goodsteel is often discarded to make the necessary weight, therebysubstantially reducing the overall yield of the product. In practice itis often necessary to provide 5,000 pounds of steel to obtain a 1,000pound larger slab simply because there is no flexibility for a givenmold size and a larger mold size must be used.

Steel manufacturers occasionally attempt to set disposable hot topsystems well into the ingot molds where a lighter than normal weight isobtained from a given mold size. This, however, increases the likelihoodof hot top floaters since it is difficult to secure hot top boards anyappreciable distance below the top surface of the ingot mold.

SUMMARY OF, THE INVENTION My invention increases the r ange of ingotweights from a given mold size by providing a hot top maintaining systemwhich can be set into the ingot mold in known fashion or can be retainedin place so that the upper portion of the hot top is above the ingotmold upper surface. This then maximizes ingot to slab or bloom yieldsand gives the steel provider a new range of flexibility. In addition, myhot top maintaining system decreases the likelihood of hot top floaters"by adding additional retaining means to an already acceptable hot topmaintaining system. My hot top maintaining system can be easily set inplace by the worker irrespective of the intended position of the hot topsystem in relation to the ingot mold.

My invention is an addition to the hot top maintaining system describedin US. Pat. No. 3,421,731 of which I am a co-inventor. In the systemdescribed in the aforementioned United States patent, each sideboard hasa pair of inclined grooves on the inner face near the ends thereof.Adjacent sideboards define converging grooves toward the mold corner andaccommodate a wedge means to retain the sideboards against the ingotmold walls. I have added to that system a chill wedge formed of twointesecting faces, each having a downwardly inclined distal edge toengage the wedge means while each face of the chill wedge is flushagainst the sideboard. The chill wedge is constructed to assure thesolidification of the metal at the comer formed by the intersectingfaces which is in alignment with the corner formed by the adjacentsideboards.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an elevation of a hot topsideboard;

FIG. 2 is an isometric through an ingot mold corner showing theconstruction of my hot top maintaining system;

FIG. 3 is an isometric of my chill wedge;

FIG. 4 is a section taken along section lines IVIV of FIG. 1;

FIG. 5 is an isometric showing the support structure for my hot topmaintaining system;

FIG. 6 is an isometric of a modified chill wedge; and

FIG. 7 is an isometric of an ingot mold corner showing a modified formof my hot top maintaining system.

DESCRIFT ION OF THE PREFERRED EMBODIMENTS The hot top maintainingsystem, generally designated 10, cooperates with an ingot mold 11 toprovide a reservoir of liquid metal which fills the cavity formed duringsolidification of certain metals such as killed steels. The ingot mold11 is normally four sided and, therefore, four sideboards 12 arenormally employed to form the hot top maintaining system 10. Thesideboards are t of the disposable preformed type and the compositionthereof does not form a part of the invention.

Each sideboard 12 has a pair of grooves 14 formed on the inward facenear the opposing ends of the sideboard 12. These grooves 14 areoutwardly inclined with regard to each other, FIG. 1. Specifically, thedistance designated A between the top edge of the sideboard and the topof the groove 14 is greater than the distance designated B between thebottom edge of the sideboard and the bottom of the groove 14. The depthof the groove 14 may also be decreased along the length of the groove toincrease the wedging effect, but such a change in depth is notmandatory.

End adjacent sideboards 12 provide adjacent grooves 14 which have aresultant inclination so as to converge downwardly toward the ingot moldcorner, FIG. 2. In assembled relationship, a wedge plate 16 is insertedin the adjacent grooves 14 of end adjacent sideboards 12 so thatincreasing outward force is exerted upon the sideboards 14 as the wedgeplates 16 are moved downwardly along the grooves 14. This wedging actionforces the sideboards 12 against the respective walls of ingot mold 1 l.The sideboards 12 are positioned so that their upper portion is abovethe top surface 13 of the ingot mold 11, FIG. 2. A space 15 is formed bythe adjacent sideboards 12 in the corner positions. This space 15 isaligned with and closed off by the mold corner below the upper moldsurface 13 and is unrestrained above the ingot mold.

A chill wedge 18 is formed of two perpendicularly intersecting faces 23and 24, each having its distal edge 20 inclined inwardly atapproximately the same angle as the angle of convergence of the Wedgeplate 16 when in place, FIG. 3. The purpose of the chill plate 18 is toassure solidification of the molten metal so that it will not escapethrough the space and escape along the upper surface 13 of the ingotmold 11. For this purpose the chill plate faces 23 and 24 can be made ofa relatively thick steel but since the real need for the chill 'zone isin the corners formed by the end adjacent sideboards, I have found thata'steel rod can be secured along the intersection formed by the twofaces, thus allowing a relatively thin sheet steel to be used for faces23 and 24. A three-fourths inch steel rod spot welded on the interiorcorners of a 16 gauge mild steel chill plate has proven more thanadequate.

The distal edges engage the wedge plate 16 while the faces 23 and 24 areflush with the end adjacent sideboards 12, thereby creating anadditional wedging action which forces the sideboards 12 outward againstthe mold walls, FIGS. 2 and 4. The interior corner of the chill plate18,-including rod 19 positioned therealong, is in alignment with thespace 15 thereby providing sufficient chill to cause immediatesolidification and prevent molten metal spillage out of the space 15.

In order to facilitate supporting the sideboards 12 while the wedges 16are being installed, rods 17 are molded into the sideboard so as toextend out of the ends thereof. Other support structures, both internaland external, can be employed but rods add to the reinforcement of thesideboard itself. These rods'l7 of end adjacent sideboards 12 rest on awooden block 20 which is positioned in the corner along the uppersurface 13 of ingot mold 11, FIG. 5. To assure a perfect alignment ofthe sideboards, the block 20 has a slightly elevated section 22 so as toavoid interference between rods 17 of adjacent sideboards 12. As apractical matter, a simple block of wood can be employed and the rods 17of adjacent sideboards 12 can merely rest on one another since the totalwedging action is sufficient to maintain the hot top system in place. I

A chill wedge 25 can also be employed in which a metal fin 27 extendsrearwardly from the exterior surface of the corner of the intersectingfaces 33 and 34, FIG. 6. The fm 27 extends into the space formed by theend adjacent sideboards. The purpose of the fin 27 is to increase thechilling effect in the corner and not to totally fill the aforementionedspace.

The sideboards may be designed to include the support means as anintegral part of the board itself. Sideboards 29 are molded to includean enlarged upper section 30 which provides a shoulder 31 which rests onthe upper surface 13 of ingot mold 11 to facilitate installation ofwedge plate 16 into the grooves 14 of the sideboards 29, FIG. 7. Chillwedge 25 having a rearward fin 27 positioned in the space betweensideboards 29 is illustrated in this particular embodiment. In additionto providing the support means for installation of the hot topmaintaining system 10, the enlarged upper section 30 provides additionalinsulation for the hot top in the area surrounding the hot top systemabove the ingot mold.

I claim:

1. A hot top system for an ingot mold comprising:

A. a plurality of end adjacent sideboards each having a pair ofoutwardly inclined grooves formed on the inward face near the endsthereof;

B. means for supporting the sideboards against the ingot mold walls sothat the upper portion of the sideboards extend above the ingot mold;

C. a wedge plate insertable into adjacent grooves of end adjacentsideboards so as to converge downwardly toward the ingot mold corner andretain the sideboards against the ingot mold walls and D. a chill wedgehaving perpendicular intersecting faces, each face inclined downwardlyalong the distal edge thereof to matingly engage the converging wedgeplate, each face being flush against the adjacent sideboard and theintersection of the faces being aligned with a corner formed by the endad jacent sideboards, said wedge plate and chill wedge extending belowthe ingot top mold.

2. The hot top system of claim 1 wherein the sideboards include anenlarged shouldered upper portion resting atop the ingot mold walls toform the supporting means for the sideboards.

3. The hot top system of claim 1 wherein support bars extend out of thesideboard ends.

4. The hot top system of claim 3 wherein the supporting means comprisesblocks positioned atop of the ingot mold corners so as to support thebars extending out of the sideboard ends.

1. A hot top system for an ingot mold comprising: A. a plurality of endadjacent sideboards each having a pair of outwardly inclined groovesformed on the inward face near the ends thereof; B. means for supportingthe sideboards against the ingot mold walls so that the upper portion ofthe sideboards extend above the ingot mold; C. a wedge plate insertableinto adjacent grooves of end adjacent sideboards so as to convergedownwardly toward the ingot mold corner and retain the sideboardsagainst the ingot mold walls; and D. a chill wedge having perpendicularintersecting faces, each face inclined downwardly along the distal edgethereof to matingly engage the converging wedge plate, each face beingflush against the adjacent sideboard and the intersection of the facesbeing aligned with a corner formed by the end adjacent sideboards, saidwedge plate and chill wedge extending below the ingot top mold.
 2. Thehot top system of claim 1 wherein the sideboards include an enlargedshouldered upper portion resting atop the ingot mold walls to form thesupporting means for the sideboards.
 3. The hot top system of claim 1wherein support bars extend out of the sideboard ends.
 4. The hot topsystem of claim 3 wherein the supporting means comprises blockspositioned atop of the ingot mold corners so as to support the barsextending out of the sideboard ends.